It is the purpose of this study to describe the manifestations of the rash of erythema neonatorum in a number of newborn infants, to demonstrate the eosinophilia in the pustules, and to discuss the eosinophilia in the blood.

For many years physicians recognized the occurrence of various reactions in the neonate during his first days of extrauterine life. They were considered evidence of the newborn's functional adjustment to his new existence. They included an erythematous or papular rash, transitory edemas of the face and genitalia, a mild generalized lymphadenopathy, breast swelling and lactation, vaginal bleeding, and icterus of the newborn. Other signs, as vomiting, mucoid or loose stools, weight loss, or transitory fever, were attributed to an irritating effect of "noxious" materials in the colostrum on the unskilled gastrointestinal tract.

Lactation and vaginal bleeding are now known to result from maternal hormone stimulation. After studies of hemoglobin and excretory liver